For all the talk about starting over in the premiere of the fifth and final season of Six Feet Under, the oppressively dour mood that put the once-terrific series in a two-year rut returns with as much certainty as the cast.

The couple got engaged at last season's end and is on the brink of their wedding day. Can the popular HBO show about a dysfunctional family and its California funeral home convincingly wear white?

In addition to the wedding, a baby and plans to adopt a child are on the table for the Fisher family. David (Michael C. Hall) and Keith (Mathew St. Patrick) look forward with something resembling positivity and commitment. Even Claire (Lauren Ambrose) seems to be involved in a relatively nonexplosive relationship. A promising diversion from the series' now innate gloom and doom, no? Well, no.

Born to bicker, David and Keith squabble over adoption versus surrogate parenthood. Claire, a loser magnet with the worst dating track record in television history, is involved with Brenda's brother Billy (Jeremy Sisto), who we're often told is fine ... when he's on his meds. If there's any trouble to be found early on, it's with Ruth (Frances Conroy) and George (James Cromwell). George's mental illness, hinted at last season, prompts men-in-white and a straitjacket.

Only Federico (Freddy Rodríguez) seems marginally content, uncomfortably playing the field after his wife refused to take him back. He longs to reassemble his family, but in the interim, he serves as the one perky glow to the series.

As for the Fishers, as is often the case, the good goes bad and the bad gets worse.

This is where Six Feet Under continues to wander. Characters must develop over five seasons to maintain interest, but the SFU principles have strayed too far from the charms that won over viewers four years ago. The world has changed in that time, too, but borderline nihilism and political cynicism don't sell effectively when wrapped in whining self-pity. One of television's best ensemble casts has been handcuffed, and the first hour of the new season creates anxiety that they might not be freed.

Worst is the absence of laughs. Nate's dumb-guy charisma, David's endearing loss of his passivity, Claire's burgeoning rebellion: In early episodes, these characters gave the Fisher family an equilibrium. Both masks of drama were represented. The Fishers and their circle made poor decisions with panache, but there was always a functional voice in the dysfunctional family to point that out.

Nate has been a witless wonder for more than two seasons now, reaching a nadir last season as he screamed directions at an icy woman as to how to mourn. "I don't want to grieve anymore," he says in tonight's episode. Be my guest.

The peripheral humor is also gone. Instead of the gruff, wise-cracking elder Nathaniel Fisher (the reliably fantastic Richard Jenkins) babbling at the family from beyond the grave, we get abrasive antagonism from Lisa (Lili Taylor), the character who almost single-handedly derailed the series. No tangential character has stepped up to replace the unsettlingly and enjoyably odd Arthur (Rainn Wilson).

The funeral home is also a notable absentee. In spite of its corpse-filled chilliness, the creepy house with the creepier basement served as a neutral zone, a water cooler, a place for the characters to mix and mingle without the burden of their Job-like existence as they stitched and drained and injected and rearranged the dead. The Fisher home hardly factors into the show these days. Instead, we get self-involved characters doing what they do best.

After four seasons of the Fisher sibs knitting their frayed relationships, the only way they're able to sit down together in this episode is stoned, with all three offering their stash.

If this mood continues over the season, Six Feet Under will have suffered more bad seasons than good ones.

So Season 5 starts with one of television's biggest bummers of a wedding.

If this is the best death has to offer, I'll take taxes. At least you sometimes get something back.